Shoe-stitching machine.



H. A. WEBSTER, DECD.

C. B. WEBSTER, ADMINISTBATRIX.

SHOE STITCHING MACHINE.

APPLICATION PILEDJAN.. 13, 1906.

914,091 Patented Mar. 2, 1909.

CORA B. WEBSTER, OF HAVERHLL, MASSACHUSETTS, ADMINISTRATRX F HAROLD A.WEBSTER, DECEASED, ASSIGNOR T0 SNGLE THREAD LGCK STITCH COMPANY, 0F"

HAVERHILL, MASSACHUSETTS, A CORPORATIGN OF MAINE.

SHOE-STETVCHING- MACHKNE.

To all whom it may concern:

Be it known that HAnoLD A. l'vnnsrnn,

deceased, late a citizen of the United States, and a residentofHaverhill, in the county of ,5 Essex and State of Massachusetts,didinvent certain new and useful Improvements in Shoe-StitchingMachines, of which they monly used the construction is such that theneedle baris caused to dwell for an appreciable interval at the upperlimit of its 'i stroke, this being due in some machines to the mode ofoperation ofthe means for varyl5 ing the extent of upward movement oftheneedle bar yto correspond with different thicknesses of materialoperated upon, and inasmuch -as therthr'ead is held under tension s bythe needle while the latter is at the upper i 2O limit of its movement,this tension on the thread has necessarily been maintained for afractional part of each stroke, during which the shoe being operatedupon is caused to undergo certain movements such as feedA ing movementsand changes in the direction of the saine. The result has been not onlythat the freedom of these inovements'has been restricted by theconnection of the shoe with the needle through the loop held. by

the latter under' tension, but also that the tendency of the thread tobreak has been greatly increased, suoli breakage having been 'found verytroublesome in mairv cases.l

This invention is intended. to lovercome the liabilityto breakage of thethread in this manner, and also to increase the ease and freedom ofmovement of the shoe being stitched, and to this end means are providedwhich, without interfering with the variabil- 40 ity of the stroke ofthe needle, operate to cause the latterl to move downward for a certaindistance immediately after reaching the upper limit of its stroke,regardless of its actual position when this limit is reached.

the resultl being that the tension put uporI the looped thread by theupward movement of the needle is immediately released by a downwardmovement of the needle 1and the consequent slackening of the loop assoon as the needle bar has' completed its upward movement.

This invention may have various embodi- Specicatcn oi Letters ll'atent.

Patented March 23,

Application filed January 13, 1906. Serial No. 295,833.

sewing machine, and the illustration in the accompanying drawingscorresponds in the use of reference numerals and otherwise with thedrawings of said Richardson patent, which are here reproduced to asuiicient eK- tent to illustrate the construction and mode of operationof the parts necessary for an understanding of the resent improvement.

1n .these drawings, E'igure 1 is a perspective view of the front end ofthe head of the machine, with parts broken away. Fig. 2 is a transversesection through the same. Fig. 3 is a perspective view of a detailhereinafter described; and Fig. 4 is a sectional view illustratinganother detail.

Referring to the drawings, 3 indicates the base plate of the head of themachine and 6 indicates an upright secured thereto, in which u right isjouinaled the front end of the need e-driving shaft 8. said shaftprojecting rearwardlyltherefroml to a point where it 4receives suitablerotating means which itf'is not necessary to illustrate.

.60 represents the presser foot, `which in this machine is automaticallyadjusted according to the thickness of the work, said' presserfoot beingadjustably secured to a finger 62 projecting downwardly and laterallyfrom the lower end of a bar 6]. Said bar 61 is mounted to slidevertically on suitable guides, the guide at the upper end el' the barconsisting olY a vertical slot formed n;

said bar and a screw pin (36 passing through r.

the same into a brecha-,t (3T which is bolted `to the top of the upright(S. At its lower und said bar G1 guided `by a llangcl'l plate 5S securedto the side of the base plato Il. Near the base plate the bai-151 isformed with a shouldn/1170 and to the sido of the bar above saidshoulder is secured a clip Tl having a shoulder confronting that at 7U.Between l these shoulders is provided a space for the M es reception ofa pin 72 which projects forwardly from an arm 73 rigidly secured to ashaft 74, said shaft being .'ournaled in bearings aorded by the uprightscarried by the head ci the machine.f

The stitching needle is shown at 105 and is clamped in the lower end ofa needle bar 106 by a clamp 107, said bar 106 being arranged toreciprocate vertically in guides carried res actively by the bracket 67and the base 'o ate 3. Onthe 'forward end of the shaft 8 is mountedacrank pin 109 which isconnected bya link 4110 with a lever 111, thelatter being. fulcrumed .on a collar 112 rigidly secured to the needlebar, this pivotal connection of said lever to the collar 112 ermitting acertain amount of free play'or ost motion between the crank pin and theneedle bar. The collar 112 is provided with two lugs 113and 1111 sopositioned that when the link 110 descends, the lever 111 swingsdownward il. "ely until it encounters the lug 1.13 without effecting anydownward movement of the needle bar. The continued movement of 4thislink, however, ,after the lever 1 11 4strikes the lug 113, causes theneedle bar to move downward, which downward movement always stops ateitactly the same point. ,v

For determining the upward movement oi the needle bar there is provideda lever 115 ulerumed upon a fixed stud 115 andhaving its end 117extending forward into the ath of the free end of the lever 111. Saidever i116 is ulcrumed between its ends, and its shorterv arm 118`projects downward and rests against a stop bar 119 adjustably securedby screws .120, 121 to the arm 73, a spring 122 being attached to saidarm 118 and to the upright d so that said arm is aln ways held againstthe end oit the stop bar 119. The osition of the arm 73 is variedautomatica ly accordin to thef thickness of the work upon which t epresser foot rests, and hence the lever 116 is correspondingly adjustedabout its fulcrum, so that the end 117 thereot1 is adapted to serve as avariable inlcrum for the ever 111 on the upstroke of the needle bar. Theinitial upward movement ot the needle bar may be caused by theengagement of the lever 1 1 1 with the lug 114, but as soon as the endoi said lever comes in contact withl the part 117 the fulcrum point isimmediately changed and the needle bar moves still fartherupward with arapid movement, the limit ofthis upward movement varying inversely withthe height of the iulcrum 117 trom the base plate 3. The result of thisarrangement is that the movement oi the needle bar is not continuous, inthat said bar' dwells for a certain interval at each end ci' its stroke,the position reached by this needle bar at the upper limit' oi' itsstroke being also variable. A piece oi friction material 500 is:inserted between the einem upper portion oi the needle bar and the arm67 Jior the purpose ci O'iering a sufficient resistance to the movementoi said bar to hold it stationary at the limit of its upward movement,the pressure of this friction material on the ba-r being variable bymeans oi an adjusting screw pin 1601.

123 is the cast oil', which is secured u on the endof a narrow bar 1241mounte to slide inra groove in the needle' bar 106. At its upper endsaid bar projects from said groove at 125 and is connectcdliy a spring126 with the collar 11'2. Another collar 127 surrounds the needle barbetween the projecting end 125 andthe top of the collar 112, whichcollar 127 is provided with an upwardly-extending arm 128 passingbetween the bracket 67 and a piece oi' friction material 129, heldagainst said arm by a clip 130. The needle bar also carries a stud orclip 1311 located a short distance above the collar 112, so that thecast-oil has a c rtain amount of lost motion at each recipro ation oithe needle bar, said clip 1311 servil g as a stop to engage the collar127 and ferrie the same positively downward after a `limited relativedownward movement ci the needle bar has occurred.

The feeding mechanism comprises a point 131 secured to an arm 131i,which arm is pivotally secured to the lower-end oi' a bar 133, theillustration of the connections betweenthis feeding mechanism and theother parts and the 'means for operating the same being immaterial tothe present invention.

The construction and operation ci the parte above described are the sameas shown and described in the Richardson patent previously referred to,and it will be seen that as, thus constnfffted the needle bar will becaused to dwell for a certain interval after it reaches ie limit of itsupward. movement by reason of the free play allowed to the lever 111between one or the other of the upperv iulcrums or stops 114 and 117, asthe case may be, andthe lower stop 113, which dwell will vary accordingto the adjustment of the stop bar 119 on the lever 73 and also accord,

ing to the thickness of the work. According to the present inventionmeans are provided for preventing` this dwell by causing the needle barto move downward immediately after reaching said upper limit oi itsmovement as last as such downward movement is permitted by the partsalready described for operating said bar, and in the present instancethe invention is. illustrated as embodied in an attachment adapted to beapplied or added to the parts already described, which attachmentcomprises a bracket a adapted to be bolted to the top of the bracket-6-7, and av spring-pressed member b mounted in said bracket atomove'vertically in such a position that when the needle bar approachesthe limit of its upward movep iii-an amic extendinghorizontally from the4 einem' ment, it will engage said member t and lift the s ameagainstthe pressure of its actuating vsp1ing,so that as soon as theneedle bar is 'struction herein represented, said s ringpressed member bconsists of a p unger mounted to slide vertically near its lower endbracket @directly above the-needle bar, and also mounted .at-its upperportion to slide in a sleeve d 'passing vertically through an-'` otherhorizontal -arm e' extending from said bracket (1 'and' externally screwthreaded and provided with a head f so as to be' capa` ble of'verticalfadjustment in said bracket.

lA collar g rigidly secured to the plunger b above the arm C and servesas a stop to limitthey downward movemei'itof said plunger, andabove'said collar a spiral 'spring 7i surrounds the plunger and :bearsatits ends .o u onfsaid collar and upon the lower end of t e sleeved,vwhich spring is adjusted by means of said sleeve to give a sufficient'-downwardxpressure to` overcome the frictional 4resistance afforded bythe friction vdevice 600. 'As'thus constructed, when the .needle barmoves upward iteventually` comesin contact .with the low'er end of thelplunger b andllifts the latter with it during the remainder of itsupward movement, at the'end of which movement' said plunger limmediately operates to force the needle bar viously veX lained V1down-ward until fthe stop collar .g comes in l slackeningtheloopxheldvby the needle and contact with ,the arm c, thus immediatelyrelieving the tension on the thread aspra It will, e observed that thelriieans` i"er forcing the needle barfdownward immedi at'ely after itreaches the limit of: its upward movement act independently ofthe meansfor raising the needle barthrough a variable distance and for forcing itthrough the work heingoperatcd upon, that is to say, the construction issuoli that the adjustment or variation of the upward 'stroke of' theneedle bar is not .interfered with and it is to be understood that whileit is convenient-and desirable in most cases to embody the prese eutimprovements in the form of an attachment which can be applied toexisting ma chinas, yet such an arrangement is not essential, since theinvention may be variously constructed and modifiedv and may be.embodied in the structure of the stitching I machine itself, whether ofthe type herein represented or of other types such as are wellA` knownin the art.

Vl'hat is claimed is: 1. In a stitching machine, the ccmi'rina- -tion ofa needle bar and reciprocating ineens therefor, means foi' varying theupward stroke of said bar, and meanssuppleinental4 to said reciprocatingmeans for moving said bar downward'immediately after it reaches Athelimit of itsupwaid movement.

'stroke of said bar, and a spring-pressed member operating independentlyof said reciprocating' means to force the needleba'r downwardimmediately after it reaches "the limit of its upward movement.,

' 3. In a stitching. machine, theI combination of a needle bar and meansfor operating the same, said means permitting a dwell of said bar at thelimit of its upward movement,

-and means nsupplemental to said operating means for causing a downwardmovement of the needle har immediately after it reaches said limit.

4. In a stitching machine, the combination of a needle bar and means foroperating the'saine, said means having 'a freedownward movement aftersaid bar has reached the limit of its upward movement, and means forcausing-said needle bar to follow said operating means downward duringthe free movement of the latter.

5, in a stitching machine, the combina# tion of a needle bar and meansfor operating the same, said means permitting said bar tov dwell lat thelimit 'of its upward movement, and a spring-pressed member located inthe path of the upward movement of said bar and operating to engage saidbar and force the saine downward after it reaches said limit ofupward-movement.

6; In a stitching machine, the combination of -a needlebar and.reciprocating devices therefor, a presser foot mechanism, and meanscontrolled tlierebyfor effecting the variable upward movement of saidbar, said means permitting a dwell ofthe har at the limit of its upwardmovement, and supplementary means for forcing said bar downicowardimmediately after it reaches said limit.

7. An attachment for stitching machines, comprising a bracket, avertically-inovable member carried thereby. and adapted to be located inthe pathl of upward movement of a needle bar, and means for exerting adownward .pressure on said vertically-movable member. l

8. Anattaohnient for stitcl'iinglmachines, comprising a bracket, aplunger mounted t'o cated in the path of upward movement of the needlebar, and a spring constantly tending to force said plunger downward.

9. An attachment for stitching machines, comprising a bracket, a plungermounted to slide vertically therein and adapted to be located in thepath of upward movement of the needle bar, a spring constantly tendingto force said plunger downward, and means for varying the pressureexerted. by said spring.

vslide verticallytherein-and adapted to be lol ist.

10. An attachment for stitching machines, comprising a bracket adaptedtobe secured to the bead of a stitching mecliine, and provided With armsextending' horizontally over the needle bar, a threaded sleeve mountedin one of said arms and vertically adjustable therein, a plunger mountedto slide Vertically in the other horizontal arm. and in said sleeve, estop collar carried by said plunger, and e springlocated between saidstop coller and adjustable sleeve, and acting to apply e downwardpressure to. seid plunger, sub stantially :is described..V

Signed at, l'lziverliill, twenty-sixth dey of December, 1%5.

@om B. WEBefrgERf,

uid/fm'ntstmt'm' of 'the estate of Herold fl. 'Wefl ster.

Witnesses y f, l

ROBERT D. TRASK, AQHSA E. TRASH.

Messechusetts), th-

